1. Field of the Invention
The present invention relates to the field of displays in which a head-mounted display device is combined with a display such as a liquid crystal display device (LCD) provided in an electronic apparatus.
2. Description of the Related Art
Liquid crystal display devices (LCDs) are used to display various types of data in a numerical controller that controls machining tools. Displays which use LCDs are generally used. Moreover, the contents of a plurality of windows are displayed using one LCD. Further, in order to display the contents of a number of windows which cannot be displayed on one LCD, a plurality of LCDs is used to increase the number of contents displayed on the windows.
The window mentioned herein is a window displayed on a screen display of a numerical controller that controls machining tools. Examples of such a window include a system configuration window, a diagnosis window, a waveform diagnosis window, and an alarm window. Moreover, the window is a window displayed on a screen display of a personal computer (PC). Examples of such a window include a window displayed by spreadsheet software and a window displayed by document creating software.
Moreover, as one form of display devices, a head-mounted display device mounted on the head of a human body is known as disclosed in Japanese Patent Application Publication Nos. 2014-186089, 2013-73070, 2013-258614, 2013-255102 and H10-334274, Japanese Translation of PCT Application No. H9-508478, Japanese Patent Application Publication Nos. H9-197336 and H5-91582, and Japanese Patent No. 5216761.
When the contents of a plurality of windows are displayed, there is a limit on the number of contents displayed, and the size of a display becomes too large. Moreover, when a plurality of displays is used, the area in which these displays are placed increases. For example, in the case of machining tools in a factory, it is originally difficult to use a plurality of displays in a small machining tool and the costs may increase.